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Discussion Starter · #1 ·
... or is it just in my head?

We had the final recall update performed a few weeks ago. Since, I know how to limit charging to 90% on my own, we never bothered with the interim fix. After the final recall-update/fix, we think we are having substanitially less regenerative braking when in "L" mode. Before the update, I felt that the car was akin to driving a manual shift car in which you down-shift for compression braking when slowing down, e.g., to go around a corner or to descend a hill. Now, not so much.

Case in point: We live in a hilly neighborhood. My wife commented on how on one particular hill, she never had to apply the brake before. Now she had to ride the brake. She even double checked that she was in "L" and not "D" because to her, it felt like the latter.

We never charge beyond 90%, in part because of the many hills in the neighborhood.

This is on a 2019.

Anyone else?
 

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2021 chevy bolt premier ev
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... or is it just in my head?

We had the final recall update performed a few weeks ago. Since, I know how to limit charging to 90% on my own, we never bothered with the interim fix. After the final recall-update/fix, we think we are having substanitially less regenerative braking when in "L" mode. Before the update, I felt that the car was akin to driving a manual shift car in which you down-shift for compression braking when slowing down, e.g., to go around a corner or to descend a hill. Now, not so much.

Case in point: We live in a hilly neighborhood. My wife commented on how on one particular hill, she never had to apply the brake before. Now she had to ride the brake. She even double checked that she was in "L" and not "D" because to her, it felt like the latter.

We never charge beyond 90%, in part because of the many hills in the neighborhood.

This is on a 2019.

Anyone else?
If you have a full battery you won't have the regen working as there is nowhere for the extra charge to go, you end up using the normal friction brakes
You living on a hilly terrain you should charge less, you will make up the charge on the trip downhill
 

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Discussion Starter · #4 ·
If you have a full battery you won't have the regen working as there is nowhere for the extra charge to go, you end up using the normal friction brakes
You living on a hilly terrain you should charge less, you will make up the charge on the trip downhill
We do that. Never more than 90% unless we are planning a long day trip. This is a before and after comparison. Unfortunately, I did not know that this was going to happen on the recall fix or I would have done a more scientific test with before and after data. Now I have to go by what I feel and recall.
 

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12/16 build, 2017, white LT
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We do that. Never more than 90% unless we are planning a long day trip. This is a before and after comparison. Unfortunately, I did not know that this was going to happen on the recall fix or I would have done a more scientific test with before and after data. Now I have to go by what I feel and recall.
The maximum regen is 70 kW. You could drive on a clear stretch of highway and do full regen, in L, plus paddle, and see if it is still there.
 

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2020 Chevrolet Bolt
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We do that. Never more than 90% unless we are planning a long day trip. This is a before and after comparison. Unfortunately, I did not know that this was going to happen on the recall fix or I would have done a more scientific test with before and after data. Now I have to go by what I feel and recall.
See my reply in the other thread.
 

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Volt, Polestar 2, R1T, Livewire One
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... or is it just in my head?

We never charge beyond 90%, in part because of the many hills in the neighborhood.
The recall resets your target charge level to 100%. I would be incredibly surprised if your problem was anything but this. You just have to set the target charge back to what you want it to.
 

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Discussion Starter · #9 ·
No change in regen after final fix.
So, I guess it is just me. I am going to charge the car to 100% (to see if a recalibrate changes things). I noted as I set the charging now that the charge limit was, in fact, 100%. So, I am pretty sure we have done at least one charge to full. But I am not certain as the charging may have been interrupted before completing. Then, I will do a more rigorous test at around 80% SOC to see what regenerative braking we observe.
 

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I do notice the regen is a little less aggressive than before the recall, I drive by usual route to work, at the end of my drive (therefore, not at full charge), there is a small downhill section, I used to have to feather the throttle to go down the hill, my car will roll to a stop if I don't (in L). Now I can just let go the gas pedal and my car will roll down the hill and maintain speed. So there is definitely a different regen map. Maybe the regen rate still the same, but less aggressive.

Also, I notice the windshield washing function has been updated too. The wiper used to wipe a couple time after the fluid sprayed, it's wipe much more than just twice now, which is much nicer.
 

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I do notice the regen is a little less aggressive than before the recall, I drive by usual route to work, at the end of my drive (therefore, not at full charge), there is a small downhill section, I used to have to feather the throttle to go down the hill, my car will roll to a stop if I don't (in L). Now I can just let go the gas pedal and my car will roll down the hill and maintain speed. So there is definitely a different regen map. Maybe the regen rate still the same, but less aggressive.

Also, I notice the windshield washing function has been updated too. The wiper used to wipe a couple time after the fluid sprayed, it's wipe much more than just twice now, which is much nicer.
I can understand how a battery-related software update might affect regenerative braking. I have a hard time understanding why it would change the windshield wipers.

Also, what is your target charge level, and how far is your drive to work? If you charge to 100%, your regenerative braking might be limited for as much as 24-36 miles (10-15% state of charge).
 

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The BMS is what is updated in the fix. The BMS can set a limit on max regen, but it does not control regen itself. It seems unlikely to me that a BMS update could change the “feel” of regen other than by setting a visible regen limit. If it did change the regen feel, a lot more people would be talking about it.
 

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Had the software update this morning. The regen seems totally normal, and will hit 70 kW easily. But that was only at 40% SoC on the way home. I am now charging to hilltop. May charge to 100% tomorrow morning at drive it down 25% SoC, and try an EVgo DC fast charger.

I tried an Electrify America at 37.6% DIC SoC, and it wouldn't put out more than 14 kW!

Product Font Rectangle Technology Screenshot
 

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2022 Bolt EUV Premier, No Options
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So, I guess it is just me. I am going to charge the car to 100% (to see if a recalibrate changes things). I noted as I set the charging now that the charge limit was, in fact, 100%. So, I am pretty sure we have done at least one charge to full. But I am not certain as the charging may have been interrupted before completing. Then, I will do a more rigorous test at around 80% SOC to see what regenerative braking we observe.
Bolded text above explains why your regen seemed reduced. Because it was!
 

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Just returned from my appointment to get the final update. No noticeable difference in regen.

Volt Data #1: 3.83
Volt Data #2: 3.83
Volt Data #3: 3.81

So, healthy battery, happy owner... until...

SOC: 67% when I arrived, no idea when I got home, my OnStar account is hosed because I called about the +5 year deal and now they have de-linked my car from my account, while the recall update was being applied! Boy are they going to get an earful in a few minutes!
 

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Discussion Starter · #16 ·
Bolded text above explains why your regen seemed reduced. Because it was!
No it does not. The charge limit limits how much charge can go into the battery when it is charging. The regenerative braking is reduced when the battery is full. When I was driving the car and noticing a less aggressive regenerative braking, the SOC was no where near 100%. Probably between 20% and 80%.

However, what MichBolt pointed out does.

See my reply in the other thread.
Look for that indicator on the right side of the speedometer. If it's green and you feel that regen is less, then you could say that regen has changed. If it's grey, then something else may be going on - state of charge, temperature, etc.

Edit: If you never charge above 90%, it may be worth charging to 100% at least once. There's been some discussion on this forum that the battery management system may only recalibrate at 100% state of charge. There have also been a couple of other recent posts by owners (here and here) suggesting that their displayed state of charge looks wrong after having their Bolt serviced. One was with a recall, one was with a different service (non-recall).
I charged to 100% and then my wife ran around yesterday on errands. This morning I took the car out and it is back to the way it always was. Thanks lieulson for a very good suggestion!
 

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Discussion Starter · #17 ·
I do notice the regen is a little less aggressive than before the recall, I drive by usual route to work, at the end of my drive (therefore, not at full charge), there is a small downhill section, I used to have to feather the throttle to go down the hill, my car will roll to a stop if I don't (in L). Now I can just let go the gas pedal and my car will roll down the hill and maintain speed. So there is definitely a different regen map. Maybe the regen rate still the same, but less aggressive.

Also, I notice the windshield washing function has been updated too. The wiper used to wipe a couple time after the fluid sprayed, it's wipe much more than just twice now, which is much nicer.
See my reply above. I recharged the car to 100% as suggested by lieulson to get the battery to recalibrate. After a little driving by my wife to get the SoC down, the regenerative braking seems just the way I remembered it. Let us know how that works out for you.
 
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